1. Field
The present technology relates to a safety element assembly for protecting a secondary battery from overheat and overcurrent.
2. Description of the Related Technology
Generally, unlike a primary battery, a secondary battery is a battery that may be charged and discharged. Secondary batteries are typically used as sources of energy for mobile devices, such as a laptop computer or a cellular phone, electric drills, electric vehicles, hybrid electric vehicles, electric bicycles, uninterruptible power supplies (UPS), and the like. Examples of the most generally used secondary batteries include a lithium secondary battery and a nickel-hydride battery. Secondary batteries can be categorized into cylindrical types, rectangular types, and pouch types according to their shapes.
A secondary battery typically includes a safety element assembly to secure safety of the secondary battery. Examples of safety element assemblies include a positive temperature coefficient (PTC) assembly, a safety vent, a current interrupt device, a thermal fuse, a shut-down separator, and the like.
Electronic devices using secondary batteries as a source of energy may be categorized into devices demanding high capacity and devices demanding high power.
High capacity secondary batteries may require use of a PTC assembly for safety. For example, mobile devices, such as a laptop computer or a cellular phone, may employ a secondary battery with a PTC assembly for safety. Meanwhile, a PTC assembly may not be necessary for a high power secondary battery. For example, a secondary battery without a PTC assembly is suitable for devices requiring high power rather than safety, such as an electric drill or an electric vehicle. Therefore, it is necessary to manufacture and manage secondary batteries according to separate standards based on whether high power or high capacity is desired.